I Recently Had Lumpectomy Surgery To Remove A 1.3 Cm

I recently had lumpectomy surgery to remove a 1.3 cm tumor from my breast. There was no cancer in the cells surrounding the tumor nor was any cancer found in the two lymph nodes that were removed at that time. My oncologist has recommended 3 weeks of radiation, and 5 years of Femara. He also said that if I were 70 they would do neither treatment. I am 6 months from 70. I have read the possible side effects of radiation and Femara. They can even in some instances cause cancer. This is my first diagnosis of cancer anywhere in my body, and I am reluctant to jump into this. Would you recommend this treatment, or just a yearly mammogram.